ABSTRACT
This study examines the application of near-infrared spectroscopy to noninvasively detect critical limb ischemia using regional hemoglobin oxygen saturation in percentage values and regional hemoglobin oxygen saturation limb-to-arm ratios. The regional hemoglobin oxygen saturation values and regional hemoglobin oxygen saturation limb-to-arm ratios were calculated in 61 patients with critical limb ischemia (group A). Measurements were performed in rest at four fixed spots at the most affected lower limb and at a reference spot at both upper arms. Similar measurements were performed in the left lower limb of 30 age-matched control patients without peripheral arterial disease (group B). The regional hemoglobin oxygen saturation values and regional hemoglobin oxygen saturation limb-to-arm ratios were significantly different at all measured spots between the groups (all p < 0.001), except for the regional hemoglobin oxygen saturation limb-to-arm ratios of the distal vastus lateralis (p = 0.056). However, a broad overlap of individual regional hemoglobin oxygen saturation values and regional hemoglobin oxygen saturation limb-to-arm ratios was found in both groups, which resulted in poor discriminative predictive value of single measurements. Single measurements of regional hemoglobin oxygen saturation values and regional hemoglobin oxygen saturation limb-to-arm ratios at all measured spots have poor discriminative predictive value in detection of critical limb ischemia. Measurement of regional hemoglobin oxygen saturation values and regional hemoglobin oxygen saturation limb-to-arm ratios at any of the measurement spots has no added value in detecting lower limb ischemia in individuals compared with current diagnostic modalities.
Subject(s)
Ischemia/diagnosis , Lower Extremity/blood supply , Oxyhemoglobins/analysis , Peripheral Arterial Disease/diagnosis , Spectroscopy, Near-Infrared , Upper Extremity/blood supply , Aged , Aged, 80 and over , Ankle Brachial Index , Area Under Curve , Biomarkers/blood , Case-Control Studies , Critical Illness , Female , Humans , Ischemia/blood , Ischemia/physiopathology , Male , Middle Aged , Peripheral Arterial Disease/blood , Peripheral Arterial Disease/physiopathology , Predictive Value of Tests , ROC Curve , Regional Blood FlowABSTRACT
PURPOSE: To assess the influence of dose on the risk of acute urinary retention (AUR) after iodine-125 prostate brachytherapy. METHODS AND MATERIALS: Between January 2005 and December 2008, 714 consecutive patients with localized prostate cancer were treated with iodine-125 prostate brachytherapy at our department. All patients completed four imaging studies: magnetic resonance imaging before and 4 weeks after treatment and intraoperative three-dimensional transrectal ultrasonography before and after implantation. The development of AUR was prospectively recorded. The evaluated treatment and dosimetric parameters included prostate volume, number of needles and seeds used, intra- and postoperative prostate edema, percentage of prostate volume receiving 100%, 150%, and 200% of the prescribed dose to the prostate, minimal dose received by 90% of the prostate volume, and percentage of the urethra receiving 100%, 150%, and 200% of the prescribed dose. Logistic regression analysis was used to examine which factors were associated with AUR. RESULTS: Of the 714 patients, 57 (8.0%) developed AUR. On univariate analysis, the following treatment and dosimetric factors were significantly associated with AUR: International Prostate Symptom Score (odds ratio [OR], 2.07, per 10-point increase), preimplant prostate volume (OR, 1.06), postimplant prostate volume (OR, 1.04), number of needles used (OR, 1.09), and number of seeds used (OR, 1.03). On multivariate analysis, the only independent predictive factors for AUR were pretreatment prostate volume (OR, 1.05) and International Prostate Symptom Score (OR, 1.76, per 10-point increase). Patients with a pretreatment prostate volume >35 cm(3) had a 10.4% risk of developing AUR compared with 5.4% for those with a prostate volume of ≤ 35 cm(3). No association was found between any of the dosimetric parameters and the development of AUR. CONCLUSION: The radiation dose, within the range studied, did not influence the risk of AUR after iodine-125 prostate brachytherapy. Prostate volume and International Prostate Symptom Score were the most important predictors of AUR.
